void main(){
  /**
   * for
   * for-in
   */
  var list=[1,2,3,4,5,6];
  for(var i=0;i<list.length;i++){
    print(list[i]);
  }
  //for-in相当于JS的for-of,i就是值，不是下标
  for(var i in list){
    print(i);
  }
}